Background Epithelial dysfunction in lungs plays a key role in the pathogenesis of acute lung injury. The beneficial effects of low potassium dextran glucose solution （LPD） have been reported in lung preservation, and LPD enables injured alveolar pneumocytes to recover. So we hypothesized that systemic administration of LPD may have benefits in treating acute lung injury. We investigated the effects of LPD on arterial blood gas and levels of some cytokines in oleic acid-induced acute lung injury in juvenile piglets.Methods Oleic acid （0.1 ml/kg） was intrapulmonarily administered to healthy anesthetized juvenile piglets. Ten animals were randomly assigned to two groups （n=5 each）： oleic acid-induced group （control group） with intravenous infusion of 12.5 ml/kg of lactated Ringer＇s solution 30 minutes before administration of oleic acid and LPD group with systemic administration of LPD （12.5 ml/kg） 30 minutes before injecting oleic acid. Blood gas variables and concentrations of tumor necrosis factor alpha, endothelin 1 and interleukin 10 were measured before and every 1 hour for 6 hours after initial lung injury.Results Compared with control group, blood pH, partial pressure of arterial oxygen to fraction of inspired oxygen ratio,partial pressure of arterial carbon dioxide, and mean pulmonary arterial pressure in LPD group were improved （P＜0.05or 0.01）. Six hours after lung injury, concentration of tumor necrosis factor alpha in lung tissue was lower in LPD group than control group （P＜0.05）. Plasmic concentration of endothelin 1 showed lower in LPD group while plasmic concentration of interleukin 10 showed higher in LPD group （P＜0.05）.Conclusions Before lung injury, systemic administration of LPD can improve gas exchange, attenuate pulmonary hypertension, decrease plasmic levels of endothelin 1, increase interleukin 10 and decrease concentration of tumor necrosis factor alpha in lung tissue in oleic acid-induced acute lung injury in juvenile piglets.
LING Feng LIU Ying-long LIU Ai-jun WANG Dong WANG Qiang
Background Young children are susceptible to pulmonary injury, and acute lung injury （ALl） often results in a high mortality and financial costs in pediatric patients. A good ALl model will help us to gain a better understanding of the real pathophysiological picture and to evaluate novel treatment approaches to acute respiratory distress syndrome （ARDS） more accurately and liberally. This study aimed to establish a hemodynamically stable and reproducible model with ALl in piglet induced by oleic acid. Methods Six Chinese mini-piglets were used to establish ALl models by oleic acid. Hemodynamic and pulmonary function data were measured. Histopathological assessment was performed. Results Mean blood pressure, heart rate （HR）, cardiac output （CO）, central venous pressure （CVP） and left atrial pressure （LAP） were sharply decreased after oleic acid given, while the mean pulmonary arterial pressure （MPAP） was increased in comparison with baseline （P 〈0.05）. pH, arterial partial pressure of 02 （PaO2）, PaO2/inspired 02 fraction （FiO2） and lung compliance decreased, while PaCO2 and airway pressure increased in comparison with baseline （P 〈0.05）. The lung histology showed severe inflammation, hyaline membranes, intra-alveolar and interstitial hemorrhage. Conclusion This experiment established a stable model which allows for a diversity of studies on early lung injury.
Background Pediatric patients are susceptible to lung injury that does not respond to traditional therapies. Total liquid ventilation has been developed as an alternative ventilatory strategy for severe lung injury. The aim of this study is to investigate the effect of total liquid ventilation on oleic acid （OA）-induced lung injury in piglets. Methods Twelve Chinese immature piglets were induced acute lung injury by OA. Twelve piglets were randomly treated with conventional gas ventilation （control group） or total liquid ventilation （study group） for 240 minutes. Samples for blood gas analysis were collected before, and at 60-minute intervals after OA-induced lung injury. The degree of lung injury was quantified by histologic examination. The inflammatory cells and the levels of IL-1β, IL-6, IL-10 and TNF-α in plasma, tissue and bronchoalveolar lavage were analyzed. Results Neutrophil and macrophage counts in bronchoalveolar lavage were significantly decreased in the study group （P〈0.05）. The total lung injury score was also reduced in the study group （P〈0.05）. The concentrations of IL-1β, IL-6, IL-10 and TNF-α in plasma, tissue and bronchoalveolar lavage were significantly reduced in the study group （P〈0.05）. Conclusions Total liquid ventilation reduces biochemical and histoloaic OA-induced luna iniurv in nialets.
